Appropriately called the Big N, the promotion comes with three bingo prize levels - silver, gold and platinum.
Silver winners can expect to receive upwards of £3,500, while the gold prize level is above the £100,000 mark.
But for anyone who achieves platinum status - the highest level possible in the game - a jackpot of £1 million currently awaits.
The game runs alongside traditional National Bingo events, the organiser states, with entry costing an extra £1 for those wishing to take part.
After getting their ticket stamped as proof of entry, these contestants are told to listen out for a second set of numbers, to be drawn alongside the main game balls.
The Big N numbers should be marked differently from the main numbers drawn, National Bingo advises.
If the player wins the national game, their level of success on the Big N is then taken into account.
At least six numbers must be matched in order to claim the silver prize, with the target rising to seven for gold status and eight for the £1 million platinum jackpot.
National Bingo notes that as the Big N prizes accumulate over time, the exact figure won is subject to change.
However, players can expect to be told an estimated figure for each jackpot level before the game begins.
Meanwhile, if more than one player nationwide achieves the same win level, the prize fund is to be shared equally between them.
And if the National Bingo game concludes in fewer than 27 calls, some Big N numbers might not yet have been called, the operator adds.
Those players who are successful may be required to prove that they are over 18 before any prize money will be awarded, the organiser concludes.
Written by Bob Bardsley.
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